PEOPLE has an exclusive first look at the episode (airing in full Tuesday), which features Swift and Antonoff, 33, creating the sound of a children’s choir. “Hit the last note … and just have it fall apart,” Antonoff tells the Grammy winner, 28, while she’s playing the keyboard.

Taylor Swift and Jack Antonoff

Taylor Swift/Instagram

“Do it again! Do it again!” Swift excitedly tells Antonoff as she dances around.

“It was so nice being friends again / There I was giving you a second chance / But you stabbed my back while shaking my hand,” she sings on the track. “And therein lies the issue / Friends don’t try to trick you / Get you on the phone and mind-twist you / And so I took an axe to a mended fence.”

Last week, the star brought her reputation pop-up experience (hosted by AT&T’s Taylor Swift NOW) to Santa Monica, California, where fans could snag merch and pose for photos in several installations including on Swift’s “Look What You Made Me Do” throne and bird cage from the song’s music video.

reputation pop-up

AT&T

AT&T video customers can watch the new series The Making of a Song on Taylor Swift NOW on DIRECTV NOW, DIRECTV (Ch. 1113) and U-verse (Ch. 1501). For more information on Taylor Swift NOW visit att.com/TaylorSwift.